Disease relevance of ECs1859

• Here, we report the crystal structure of E. coli RNase II, which reveals an architecture reminiscent of the RNA exosome [1].
• Conversely, toxicity is significantly reduced in the presence of excess RNase II [2].
• Mutants defective in ribonuclease II and polynucleotide phosphorylase demonstrated hypersensitivity to the antibiotic and showed a greater extent of 23S rRNA accumulation and a slower recovery rate [3].
• The effect of Escherichia coli ribonuclease II and polynucleotide phosphorylase was analysed on the degradation of Desulfovibrio vulgaris cytochrome c3 (cyc) mRNA [4].

High impact information on ECs1859

• Enhanced sequence searches reveal hitherto unidentified S1 domains in RNase E, RNase II, NusA, EMB-5, and other proteins [5].
• RNase II is a member of the widely distributed RNR family of exoribonucleases, which are highly processive 3'-->5' hydrolytic enzymes that play an important role in mRNA decay [1].
• The putative path for RNA agrees well with biochemical data indicating that a 3' single strand overhang of 7-10 nt is necessary for binding and hydrolysis by RNase II [1].
• We report that mRNA fragments differing from the monocistronic transcript by their 3' termini are also polyadenylated in the absence of polynucleotide phosphorylase and RNase II [6].
• Similarly, RNase D action on the E. coli tRNATyr precursor is limited, whereas RNase II causes extensive degradation [7].

Chemical compound and disease context of ECs1859

• The K+-activated diesterase activity against poly(U), which defines RNase II, cochromatographs with activity against T4 mRNA or pulse-labeled E. coli RNA successively on DEAE-cellulose, hydroxyapatite or phosphocellulose, and Sephadex G-150 columns [8].
• Northern hybridization to rRNA in cells treated with hygromycin B showed that RNase II- and RNase III-deficient strains of E. coli accumulated 16S rRNA fragments upon treatment with the drug [9].
• The position of modification in the polynucleotide chain was elucidated by comparison of the ribonuclease II/alkaline phosphatase digestion products of the substituted and unsubstituted tRNAPhe samples, and was identified as being exclusively the amino group of the nucleoside X in position 47 of E. coli tRNAPhe [10].

Biological context of ECs1859

• Polynucleotide phosphorylase and ribonuclease II are required for cell viability and mRNA turnover in Escherichia coli K-12 [11].
• A strain carrying temperature-sensitive mutations in genes for polynucleotide phosphorylase and RNase II was found upon shift to nonpermissive temperature to show higher differential synthesis rates of L14-L24 (and L5) relative to those of several L5-distal spc operon gene products [12].
• RNase R and RNase II are most active on synthetic homopolymers such as poly(A), but their substrate specificities differ [13].
• The intact S20 mRNA is, however, insensitive to attack by RNase II and polyadenylation of its 3'-end cannot overcome the natural resistance of the S20 mRNA to RNase II [14].
• Polynucleotide phosphorylase, RNase II and RNase E play different roles in the in vivo modulation of polyadenylation in Escherichia coli [2].

Anatomical context of ECs1859

• The presence of RNase II in high salt washed E. coli ribosomes: effect on circular dichroism of ribosomal complexes [15].

Associations of ECs1859 with chemical compounds

• However, whereas RNase R shortens RNA processively to di- and trinucleotides, RNase II becomes more distributive when the length of the substrate reaches approximately 10 nucleotides, and it leaves an undigested core of 3-5 nucleotides [13].
• On denaturing polyacrylamide gels RNase II appears as a single 72,000 dalton species [16].
• The degradation of poly(C) by RNase II was stimulated by spermine and spermidine, while that of poly(A) by RNase II was not affected by polyamines [17].

Other interactions of ECs1859

• RNase III also affects RNase II expression but in an indirect way [18].

Analytical, diagnostic and therapeutic context of ECs1859

• Expression, purification, crystallization and preliminary diffraction data characterization of Escherichia coli ribonuclease II (RNase II) [19].

References